depression & outpt. cardiac rehab

My question is what is the best setting to effectively screen for and diagnose depression in the cardiac disease population for cardiac rehab.? What is the best tool to evaluate depression, Ces-d (Radloff), Beck, or something else. We current use the Ces-d (radloff). It is 20 questions and the pt. usually don't fill it out properly, or quite understand it? Please share what has worked for your area.
Thanks Desiree, Rehab